Collapsible container with integrated wrap tray closure system

ABSTRACT

The present invention is a reliable, lightweight, environmentally friendly, highly reusable, highly durable, fully collapsible container for use in transporting solid and liquid materials, including those materials governed by the dangerous goods code of the UN regulations. The container employs a selectively sealed lid, a truss system for preventing bulge at the rim of the container so that the rim remains within the footprint of the lid, and an integrated closure system for securing transported contents.

BACKGROUND

1. Field of the Invention

The present invention relates generally to a collapsible, lightweight, durable shipping container for transporting and storing bulk materials and more specifically to a reusable collapsible container with an integrated closure system for secure containment of materials.

2. Discussion of Background Information

Plastic and steel drum-style shipping containers commonly retain bulk materials for transportation. These rigid drum containers often transport hazardous liquid and powder materials over long distances without any loss or seepage. Securely retaining hazardous materials in a transport drum is a highly desirable goal, but standard drums present a number of drawbacks that result in inefficiencies, lost profits, injuries and negative environmental impact.

First, standard drums are cumbersome to maneuver. Operators managing these drums typically employ specialized handling equipment designed for engaging these heavy drums and evacuating contents. Once emptied, these standard drums, such as the commonplace 55 gallon steel drum, remain heavy and cumbersome to handle and load onto and off of pallets and shipment trucks. An operator manually moving empty drums and loading them onto a flatbed for shipping to a reconditioning center for example, must move one drum at a time onto a pallet and/or into a truck bed.

Second, standard shipping drums made of steel, plastic, and aluminum, for example, occupy a significant amount of space during transport, even when the drums are empty. A standard 53 foot flatbed trailer truck can transport only 208 of the standard 55 gallon steel drums. This increases the number of trucks required to ship a large number of drums and thereby increases fuel consumption and harmful emissions associated with the carbon footprint of the shipping vessels.

In addition to causing increased carbon emissions, increased risk of injury during handling and decreased efficiency related to maneuverability, metal containers are expensive to purchase, rent and store. They are fairly large and therefore require a considerable amount of space to maintain on site. That required space could be considerable, depending upon the amount of material that must be stored and/or transported. While the storage volume of metal containers is considerable, the volume of material that is storable within multiple containers is diminished by the fact that the metal containers are generally cylindrical in nature. Cylinders generally cannot be oriented in a space-efficient manner. As such, there is a need in the art for containers that will contain a high volume of material securely and be storable in a low volume storage facility.

Some shipping container designs address issues with regard to reuse and compaction during empty transport. For example, bag containers take up much less space when not in use. Bag container, however, are of insufficient physical characteristics for transport purposes. That is, they are generally not tough enough to stand up to the rigors of movement by mechanical devices such as forklifts, accidental drops into cargo holds, stacking, etc. Moreover, bag containers are easily deformed by their contents. Bag containers, therefore, are not reliably stackable and fail to enable efficient transport or storing of voluminous materials. Similarly, collapsible boxes typically are only semi-rigid at best, tend to bow outward when filled, and are difficult to lift and stack when filled. Most collapsible boxes for industrial shipping uses are heavy assemblies of several layers of components and typically weigh at least 34 pounds when empty, which weight can cause fatigue and more serious conditions related to repetitive lifting by shipping personnel. Furthermore, these boxes incorporate cumbersome bottom flaps that require folding and securing prior to using the container. This processing step wastes valuable time in the field of operation and accordingly causes monetary losses associated with delay.

Some collapsible boxes and bags employ truss elements woven through their sidewalls to prevent the containers from bulging when filled. Puncturing the sidewall of a box or bag inherently creates a weak point at which the container could catastrophically fail under load forces. Furthermore, these trusses only prevent bulging at particular points along the height of the container and fail to address bulging at the top rim of the container that could prevent a properly fitted engagement with selectively engaged lid element. Furthermore, such lids require closure elements, such as corner ties or duct tape wrapped around the container and lid, to secure the lid to the container. Using tape to secure a lid to a corrugated box causes rapid degradation of the box during repeated application and removal of tape, which can peel off layers of the box. Furthermore tape can tear easily or loose adhesion under certain temperature and humidity conditions.

A need therefore exists for a reliable, lightweight, environmentally friendly, highly reusable, highly durable, fully collapsible container for use in transporting solid and liquid materials, including those materials governed by the dangerous goods code of the UN regulations. A need exists for such a container that employs a selectively sealed lid and an integrated closure system for securing transported contents.

SUMMARY OF THE INVENTION

The present invention solves the problems associated with efficiently and securely transporting reusable shipping containers designed for retaining bulk materials, including hazardous substances, and insuring reliable structural integrity with every use. The collapsible container has a permanently secured, collapsible wrap tray bottom, an integrated, non-destructive secure closure system, and scored sidewalls that enable an operator to collapse the container flat for compact transport and storage during periods of non-use.

One embodiment of the collapsible container of the present invention comprises a continuous rigid structure having four planar sides defining four inner surfaces and four outer surfaces. Two opposed planar sides each have a scoring line therein rendering the continuous rigid structure collapsible. The embodiment further comprises a five-walled inelastic wrap tray made of a flexible, inelastic fabric affixed to a lower portion of each the four outer surfaces and defining a bottom surface of the collapsible industrial shipping container.

In one embodiment the collapsible container comprises at least three side closure strips fixedly disposed on the outer surfaces of three consecutive planar sides, one end of each of the at least three side closure strips securely connecting to the inelastic wrap tray, the other end of each of the at least three side closure strips terminating in an inwardly facing closed retention loop positioned adjacent the top rim of the continuous rigid structure. In one embodiment, each of the at least three side closure strips comprises a closure means fixedly positioned along its length at a point below the top rim of the continuous rigid structure and above the five-walled inelastic wrap tray.

In one embodiment, the collapsible container further comprises a lid defining at least one hingedly attached flap affixed to the fourth outer surface such that a fourth inwardly facing retention loop is securely affixed between the flap and the fourth outer surface and positioned adjacent the top rim of the continuous rigid structure. In this embodiment, a system of one or more top closure straps affixed to the top surface of the lid are adapted for engaging with the attachment means.

In one embodiment of the present invention, an inelastic member passes through each of the inwardly facing closed retention loops of the at least three side closure strips and the fourth inwardly facing retention loop, thus preventing the top rim of the continuous rigid structure from bulging under load conditions.

BRIEF DESCRIPTION OF THE DRAWINGS

One will better understand these and other features, aspects, and advantages of the present invention following a review of the description, appended claims, and accompanying drawings:

FIG. 1 depicts a perspective side view of one embodiment of the collapsible container of the present invention having a closed lid.

FIG. 2 depicts a perspective side view of one embodiment of the container of the present invention having an open lid.

FIG. 3A depicts an exploded bottom perspective view of one embodiment of the collapsible container of the present invention.

FIG. 3B depicts an exploded side perspective view of one embodiment of the collapsible container of the present invention.

FIG. 4A depicts a partial perspective side view of one embodiment the collapsible container of the present invention with the lid closed.

FIG. 4B depicts a perspective top view of the collapsible container of FIG. 4A with the lid open.

FIG. 4C depicts a partial perspective side view of the collapsible container of FIG. 4A with the lid open.

FIG. 5 depicts a bottom view of one embodiment of the collapsible container of the present invention in a collapsed state.

DETAILED DESCRIPTION

The present invention solves the problems associated with standard drum-style and box-style shipping containers. The present invention provides a collapsible container that is rigid enough for stacking, storing and transporting a variety of materials. Unlike ubiquitous metal containers and standard corrugated box containers, however, the container of the present invention can be collapsed from a substantially cubic volume into a substantially flat square for easy stacking and storage. Additionally, the present invention can be securely closed without requiring the application of destructive tapes or flimsy ties. Furthermore, the present invention addresses preventing bulge at the top rim so that a lid properly engages for securing container contents, and the bulge prevention mechanism is applied without puncturing the container and creating a mode around which the container could catastrophically fail during use. The present invention thus provides numerous benefits to the user, as described more fully below with reference to the drawings.

FIGS. 1 through 3B depict one embodiment of the collapsible container 100 in a fully expanded state, positioned on a standard shipping pallet 500. In this embodiment, the collapsible container comprises a continuous rigid structure 200, an inelastic wrap tray 300 and an integrated lid 400 for sealing contents within the collapsible container 100 for shipment or storage. The continuous rigid structure 200 may be single walled. In a preferred embodiment, however, the continuous rigid structure 200 is at least double walled and made from a rigid material, such as, for example, fiberboard or corrugated cardboard or any lightweight, rigid material having high compression strength in an axial direction for withstanding the force of one or more filled and stacked collapsible containers 100 without buckling. In one embodiment, the lightweight fiberboard is coated for water resistance. In the depicted embodiment of FIGS. 3A and 3B, the continuous rigid structure is constructed from a continuous sheet of material formed into a symmetrical, four walled, square tube with open ends. Rigid structures having other symmetrical and asymmetrical tube cross-sectional shapes are contemplated by this invention, such as but not limited to, rectangular, hexagonal, and octagonal cross-sectional shapes.

The depicted square embodiment of the continuous rigid structure 200 therefore comprises four sides 205, 210, 215, and 220. The four sides 205, 210, 215, and 220 are not structurally independent, and thereby provide a fully rigid structure without a plurality of riveted, stapled or adhesively-sealed seams that would decrease structural integrity by providing zones of weakness inviting potential failure and separation of structural components under load and handling forces. Each of the four sides 205, 210, 215, and 220 is flat, or substantially planar, and each side has an inner surface parallel to an outer surface. Two opposed sides 210, 220 of the four sides 205, 210, 215, and 220 each have a scoring line 225 down the middle thereof for rendering the continuous rigid structure 200 collapsible into a flattened, substantially planar structure as further described herein. The scoring lines 225 need not be down the middle of their respective planar surfaces as long as they are parallel to one another, or otherwise properly aligned, for enabling compact collapse of the collapsible container 100 into a planar structure that is easily and compactly stacked, handled and stored. Certain tubular cross-sectional shapes, such as triangular, for example, may require offsetting the scoring lines 225 to achieve a flattened, substantially planar collapsed container.

The scoring lines 225 allow a user to collapse and store the present invention in the minimum amount of space while maintaining the structural rigidity of the collapsible container 100. For example, in one embodiment of a thirty-six (36) inch cubic volume collapsible container, a standard fifty-three (53) foot shipping truck transports eight hundred and forty (840) collapsed units as opposed to five hundred and sixty (560) empty units of a comparably sized, standard triple-walled shipping box. The outstanding compacting capabilities of the collapsible container 100, and the reduced weight per double-walled collapsible container 100, as compared to standard triple-walled shipping containers, therefore reduces shipping fuel costs because fewer required shipping trucks are required for transporting empty, reusable containers. In the described embodiment of the present invention, a single collapsible container 100 weighs approximately only twenty (20) pounds as opposed to a similarly dimensioned, standard triple walled shipping box weighing thirty-four (34) pounds. This lightweight design facilitates efficient and safe transport and handling, particularly by personnel porting empty collapsible containers 100 onto and off of shipping pallets.

In all embodiments, successful repeated collapse and compaction and of the present invention relies on proper placement and design of the scoring lines 225. The scoring lines 225 are not sufficiently deep so as to damage or diminish the structural integrity of the continuous rigid structure 200. In other words, the scoring lines 225 do not pass all the way through the double-walled thickness of the continuous rigid structure 200, but merely provide a point of flexure at which to collapse the collapsible container 100 when empty. In fact, the scoring lines need not be cuts at all and may be compression lines running down the length of the inner and/or outer surfaces of at least two opposed planar sides 210, 220 of the continuous rigid structure 200. In one embodiment, the scoring lines 225 are applied on the outer surface of two opposed sides 210, 220 of the four sides 205, 210, 215, and 220 and in another embodiment the scoring lines are applied to the inner and outer surfaces of two opposed sides 210, 220 of the four sides 205, 210, 215, and 220 without connecting to form a full cut or full compression. In one embodiment, for example, a cut forming scoring line 225 may penetrate one third of the way or less into the thickness of a side 210, 220 and preferably penetrates a quarter of the way or less into the thickness of a side 210, 220. In another embodiment, the scoring lines 225 may be areas of compression where the continuous rigid structure 200 is indented and completely flattened from one or both sides. In a preferred embodiment of the present invention, the scoring lines 225 are linear areas of compression at which the continuous rigid structure 200 is indented from only one side (e.g. the outside surface of two opposing sides 210, 220) by a platen press, for example. Preferably, the continuous rigid structure 200 is indented and completely flattened by the one-sided pressing process.

Turning back now to the formation of the collapsible container 100, the continuous rigid structure 200 requires the addition of a bottom surface for retaining contents. Requiring no fiberboard bottom further assists in reducing the weight of the collapsible container 100 by at least thirty percent (30%) as compared to triple-walled fiberboard containers of comparable size, which typically comprise overlapping bottom flaps that require tedious folding, assembly and securing to form a bottom. Furthermore, as already indicated, the reduction in weight adds to ease of use in the field and a reduction in freighting cost per container. The bottom of the collapsible container 100 is established by assembling the continuous rigid structure 200 with the inelastic wrap tray 300 which has four walls 305, 310, 315, 320 and a flexible, collapsible bottom member 325 extending between and connecting the four walls 305, 310, 315, 320. The flexible, collapsible bottom member 325 eliminates the need for the continuous rigid structure 200 to comprise a solid, weighty bottom surface requiring time-consuming, inefficient assembly.

Unlike shipping containers having flaps for folding in place to form a bottom surface, the present invention requires no complex or time consuming assembly to establish a bottom surface. The bottom member 325 of the wrap tray expands automatically during expansion of the collapsed continuous rigid structure 200 and entirely eliminates the hassles associated with bottom flaps, which frequently pop open during use and stick out during use and compaction. Such extraneous members typically incur damage during processing for reuse. For example, processing a typical folding container for reuse often tears away or otherwise dings, cuts or bends the bottom flaps, thereby rending the container structurally deficient and incapable of reuse.

By design, the inelastic wrap tray 300 of the present invention eliminates the risks and hassles involved in folding, unfolding and handling bottom flap members. Furthermore, the inelastic wrap tray protects the continuous rigid structure 200 from handling damage and environmental wear, thereby extending the life of the collapsible container 100. The inelastic wrap tray 300 is a five walled tray made from a collapsible, water resistant, tear resistant, inelastic material such as, but not limited to woven polypropylene, woven polyurethane, reinforced polyethylene, woven fiberglass, and other polymeric materials. The four walls 305, 310, 315, 320 of the inelastic wrap tray 300 coincide with the four sides 205, 210, 215, 220 of the continuous rigid structure 220 and are fixedly adhered thereto with adhesive or some other attachment means for securing the inelastic wrap tray 300 to the continuous rigid structure 200. The inelastic wrap tray 300 may be, for example, shrink wrapped, adhesively affixed, riveted, stapled or press fitted to the outer surfaces of the four sides 205, 210, 215, 220 of the continuous rigid structure 200.

In one embodiment, assembly requires placing the continuous rigid structure 200 is placed into the inelastic wrap tray 300 in a compressed state with the continuous rigid structure 200 abutting the inner surface of the bottom member 325 of the wrap tray 300, and then expanding the continuous rigid structure 200 so that the outer surfaces of the four sides 205, 210, 215, 220 abut the inner surfaces of the walls 305, 310, 315, 320 of the inelastic wrap tray 300. An adhesive may be applied across one or both of the outer surfaces of the four sides 205, 210, 215, and 220 and/or inner surfaces of the walls 305, 310, 315, 320 of the inelastic wrap tray 300 prior to insertion or expansion. In one embodiment, adhesive is applied uniformly across the entire outer surface of each of the four sides 205, 210, 215, 220 of the continuous rigid structure 220. In another embodiment, adhesive is applied to each outer surface of each of the four sides 205, 210, 215, 220 along the perimeter of the area covered by the walls 305, 310, 315, 320 of the inelastic wrap tray 300. In yet another embodiment, the outer surfaces of the four sides 205, 210, 215, 220 and inner surfaces of the walls 305, 310, 315, 320 are spot tacked together. In one embodiment, less adhesive or no adhesive may be applied when the inelastic wrap tray 300 is tightly fitted to the continuous rigid structure 200 such that compressive forces and/or frictional forces securely bind the two components to prevent separation or slippage during use. However, in all embodiments, applying adhesive uniformly across all of each outer surface of the four sides 205, 210, 215, 220 and/or inner surfaces of the walls 305, 310, 315, 320 prevents the inelastic wrap tray 300 from warping and wrinkling during use and prevents slippage between the inelastic wrap tray 300 and continuous rigid structure, especially following regular collapse and reuse.

The inelastic wrap tray 300 therefore is sized and shaped to accommodate the continuous rigid structure therein, while providing a flexible, collapsible bottom member 325 to the collapsible container 100. Preferably, the lower rim 223 of the continuous rigid structure 200 rests on the flexible, collapsible bottom member 325 of the inelastic wrap tray 300 so that the continuous rigid structure 200 is tightly confined therein and adds compression strength along the entire height of the walls 305, 310, 315, 320 of the inelastic wrap tray 300. In one embodiment, the walls 305, 310, 315, 320 extend the full height of the four sides 205, 210, 215, 220 of the continuous rigid structure 200, and in another embodiment depicted in FIGS. 1 and 2, the walls 305, 310, 315 320 extend up to about half the height of the four sides 205, 210, 215, 220 of the continuous rigid structure 220. This reduces both overall weight and component costs associated with the assembled collapsible container 100. This configuration also increases ease of assembly in slip fit embodiments of the collapsible container 100 wherein the continuous rigid structure 200 is slipped inside the taught, tightly fitted inelastic wrap tray 300, with or without adhesive disposed therebetween.

In one embodiment, the inelastic wrap tray 300 further comprises at least one attachment tab 330 secured at the outer junction of one of one of the walls 305, 310, 315, 320 and the bottom member 325 and enabling handling personnel to securing the collapsible container 100 to a standard shipping pallet by attachment means such as, but not limited to, a nail, staple or non-permanent adhesive. The one or more attachment tabs may be manufactured of the same type of material from which the inelastic wrap tray 300 is manufactured and may be stitched, welded, riveted, stapled or otherwise permanently and securely fastened to the inelastic wrap tray 300.

The inelastic wrap tray 300 protects the continuous rigid structure 200 from damage from the elements and damage associated with shipping and handling. Additionally, the inelastic wrap tray 300 assists the continuous rigid structure 200 with resisting radial or expansion forces and preventing bulging during use, shipping and handling. As indicated above, the inelastic wrap tray 300 may be a material such as, but not limited to, woven polypropylene, woven polyurethane, reinforced polyethylene, woven fiberglass, and other polymeric materials. Preferably the material comprising the inelastic wrap tray 300 has a low modulus of elasticity and therefore contributes to the high bulk modulus of the collapsible container 100 of the present invention. The fibers of the inelastic wrap tray 300 preferably exhibit high shear strength so as to withstand radial (i.e. expansion) forces and axial compression forces both under load and under compression while the inelastic wrap tray 300 remains supple enough to avoid fiber degradation and shear strength degradation after repeated use, compaction, and collapse of the collapsible container 100.

For example, an inelastic wrap tray 300 extending half the height of the collapsible container 100 and comprising woven polypropylene, assists in counteracting radial expansion forces in a standard UN drop test of a loaded, cubic thirty-six (36) inch double walled fiberboard embodiment of the collapsible container 100. Subjecting the described embodiment of the collapsible container 100 of the present invention to a standard UN drop test qualifies the collapsible container 100 for a PG 1 rating for transport of solids at 2500 pounds and a PG II/III rating for transport of solids at 2500 pounds, and this embodiment of the collapsible container 100 therefore qualifies for bearing an 11 G UN marking. The fabric of the inelastic wrap tray 300 therefore reinforces the corners 201, 202, 203, 204 of the continuous rigid structure 200 and keeps the collapsible container 100 from splitting open during a standard, required UN drop test for industrial shipping containers.

In addition to the support provided by the inelastic wrap tray 300, a lid 400 protects the contents of the collapsible container 100. In one embodiment, the lid 400 is made of coated, singled walled fiberboard that is both water resistant and lightweight. Preferably, in all embodiments, the lid 400 is formed of a solid, single piece of fiberboard, and therefore enables sealing the collapsible container 100 a single closure step and providing optimum coverage of content retained within the collapsible container 100. In the embodiments depicted clearly in FIGS. 1, 2 and 5, the lid 400 comprises at least one hingedly attached flap 405 that is affixed to the outer surface of one of the four sides 205, 210, 215, 220 of the continuous rigid structure 200. As depicted clearly in FIGS. 1 and 2, the hingedly attached flap 405 is secured adjacent the top rim 222 of the continuous rigid structure 200 such that a hinge 407 of the lid 400 aligns with or rests just above the top rim 222. In one embodiment, the hinge 407 is a score line or area of compressed fiberboard. The hinge 407 may be formed, for example, by compressing and flattening the fiberboard of the lid 400 from one or both sides, thereby enabling flexure along that line or area of compressed material. Formation of such a hinge 407 enables a user to flip the lid 400 forward or backward to cover and uncover the contents within the collapsible container 100 with little effort and only a single movement.

In one embodiment, depicted in FIGS. 1 and 2 for example, the hingedly attached flap 405 is adhesively affixed to the outer surface of one planar side 205 of the continuous rigid structure 200, thereby forming a “hinge side” of the collapsible container 100. The hingedly attached flap 405 may be secured to the continuous rigid structure 200 in other ways such as, but not limited to, stapling and riveting, or in another embodiment, the lid 400 maybe constructed from the same, single piece of material forming the continuous rigid structure 200 so that the two components are formed as a single, monolithic structure. In one embodiment, best shown in FIG. 4A, the lid 400 may comprise one or more additional flaps 410, 415, 420 that are independent of one another, having a gap therebetween at each corner of the lid 400. Maintaining the hinge side flap 405 and the one or more additional flaps 410, 415, 420, as independent members enables flattening the entire assembly upon collapse of the collapsible container 100. In this embodiment, upon collapse, the lid 400 folds back at the hinge side to rest face-to-face upon the outer surface of the planar side 205 to which it is attached, thereby exposing the bottom surface 430 of the lid 400. All flaps 405, 410, 415, 420 splay and lie flat, as shown in FIG. 5.

Turing now to securing the lid 400 in a closed position, in one embodiment, the lid 400 is reinforced with a system of one or more top closure straps 435, 440 affixed to the top surface 425 of the lid 400. The one or more top closure straps 435, 440 are positioned to engage with one or more side closure strips 250, 255, 260 disposed on the outer surfaces of the continuous rigid structure 200. In one embodiment, the system of top closure straps comprises a first top closure strap 435 affixed to the top surface 425 of the lid 400 such that both free ends hang beneath the closed lid 400, and a second top closure strap 440 crisscrossing the first closure strap and having a first end affixed to the inelastic wrap tray 300 and a second end hanging freely beneath the closed lid 400. The second top closure strap 440 may be affixed to the inelastic wrap tray by any means such as, but not limited to stitching, gluing, riveting, or stapling. In a preferred embodiment, the second top closure strap 440 is securely stitched onto the inelastic wrap tray 300 to prevent any give, or movement, under tension. The first top closure strap 435 and second top closure strap 440 may be affixed to the top surface 425 of the lid 400, and outer surface of the planar side of the continuous rigid structure 200, by any means such as, but not limited to gluing, riveting or stapling. Preferably the first top closure strap 435 and second top closure strap 440, are adhesively attached to the top surface 425 of the lid 400 and the second top closure strap 440 is also adhesively affixed to the outer surface of the planar side 205 on which it is disposed.

Permanently adhesively affixing the one or more top closure straps 435, 440 prevents the formation of any attachment induced holes through or divots into the single-walled lid 400 and double-walled continuous rigid structure 200 such that no zones of structural weakness are formed in those members. In a preferred embodiment, the one or more top closure straps 435, 440 are permanently adhesively affixed to the lid 400 and are wear resistant and reusable precluding the need for closing the lid with destructive tape that delaminates and degrades fiberboard upon removal. Preferably, the one or more top closure straps 435, 440 are inelastic, collapsible, durable and weather resistant, like the inelastic wrap tray 300. The one or more top closure straps 435, 400 therefore may be manufactured from one or more flexible, strong, inelastic materials such as, but not limited to, woven polypropylene, woven polyurethane, reinforced polyethylene, woven fiberglass, and other polymeric materials. Preferably the one or more top closure straps 435, 400 are flat, wide strips of material having a low modulus of elasticity, a high yield strength and little thickness so as to maintain the low profile of the collapsible container 100 and so as to prevent any snagging or tearing during handling, transport and use.

In the described embodiment having at least two top closure straps 435, 440 disposed on the lid 400, the free end of the second top closure strap 440 and the free ends of the first top closure strap 435 are adapted for engaging with at least three respectively aligned side closure strips 250, 255, 260 affixed respectively to the outer surfaces of three consecutive planar sides 210, 215, 220. The at least three side closure strips 250, 255, 260 each have a first end affixed to the inelastic wrap tray 300 and a second end terminating in an inwardly facing closed retention loop 265, 270, 275 disposed at the top rim 222 of the container. In one embodiment, depicted in FIGS. 4B and 4C, a fourth, independent inwardly facing closed retention loop 280 made of the same type or types of materials from which the at least three side closure strips 250, 255, 260 are made, is securely, permanently affixed between the hingedly attached flap 405 and the outer surface of the “hinge side” planar side 205 to which the lid 400 is affixed. The fourth, independent inwardly facing closed retention loop 280 may be affixed by any means such as, but not limited to stitching, gluing, riveting, or stapling. Similarly, and like the second top closure strap 440, each of the at least three side closure strips 250, 255, 260 is affixed at one end to the inelastic wrap tray 300 by any means such as, but not limited to stitching, gluing, riveting, or stapling. In a preferred embodiment, the at least three side closure strips 250, 255, 260 are securely stitched onto the inelastic wrap tray 300 to prevent any give, or movement, under tension. Additionally, the at least three side closure strips 250, 255, 260 are affixed to the outer surfaces of the continuous rigid structure 200 by any means such as, but not limited to gluing, riveting or stapling. Preferably the at least three side closure strips 250, 255, 260 are adhesively, permanently attached to the outer surfaces of the continuous rigid structure 200.

Permanently adhesively affixing the at least three side closure strips 250, 255, 260 prevents the formation of any attachment induced holes through the double-walled continuous rigid structure 200 such that no zones of structural weakness are created during manufacture and assembly of the collapsible container 100. The at least three side closure strips 250, 255, 260 are permanently affixed to the continuous rigid structure 200 wear resistant and reusable. Preferably, the at least three side closure strips 250, 255, 260 are inelastic, collapsible, durable and weather resistant, like the inelastic wrap tray 300. The at least three side closure strips 250, 255, 260 therefore may be manufactured from one or more flexible, strong, inelastic materials such as, but not limited to, woven polypropylene, woven polyurethane, reinforced polyethylene, woven fiberglass, and other polymeric materials. Additionally, in one embodiment, the fourth, independent inwardly facing closed retention loop 280 is manufactured from the same material as the at least three side closure strips 250, 255, 260 and their inwardly facing closed retention loops 265, 270, 275 formed at the ends thereof. Preferably the at least three side closure strips 250, 255, 260 are flat, wide strips of material having a low modulus of elasticity, a high yield strength and little thickness so as to maintain the low profile of the collapsible container 100 and so as to prevent any snagging or tearing during handling, transport and use.

Securing the lid 400 in a closed position over the continuous rigid structure 200 requires connecting the free ends of the one or more top closure strips 435, 400 to the at least three side closure strips 250, 255, 260. Each of the at least three side closure strips 250, 255, 260 comprises an attachment means located along the length of each of the side closure strips 250, 255, 260 at a point above the inelastic wrap tray 300 and below the top rim 222 of the continuous rigid structure so that a gap exists between the free end of each of the top closure straps 435, 440 and the at least three side closure strips 250, 255, 260. This enables tensioning the top closure straps 435, 440 and the at least three side closure strips 250, 255, 260 prior to connecting those aligned elements to secure the lid 400 tightly in a closed position. In the embodiment of FIGS. 1 through 3B, the free end of each of the at least three side closure strips comprise a lower eyelet 297 formed therein and each of the free ends of the top closure straps 435, 440 each comprise an upper eyelet 445 formed therein. In the embodiment of FIGS. 4A through 5, each of the at least three side closure strips 250, 255, 260 comprises an outwardly extending loop 299 formed along the length thereof and having a lower eyelet 297 formed therein. In both of these embodiments, a plurality of ties 285, 290, 295 may be looped through the lower eyelets 297 and upper eyelets 445 to secure the lid 400 to the continuous rigid structure 200 and securely seal the collapsible container 100.

Although the depicted embodiments show an eyelet and tie closure system, other means of secured closure are possible. For example, the outwardly extending loop 299 might retain therein a metal ring to which an aligned top closure strap may tie. In other embodiments, the top closure straps 435, 440 and/or side closure strips 250, 255, 260 may comprise a buckle closure system or snap-lock closure system with one component of each mating system disposed on each top closure strap 435, 440 and the other component of each mating system disposed on or integrated with each of the at least three side closure strips 250, 255, 260. In these alternate embodiments, the top closure strap 435, 440 and at least three side closure strips 250, 255, 260 may be longer or shorter than depicted in the embodiments of FIGS. 1 through 3B and 4A through 5, depending on the type of closure mechanism implemented.

In addition to contemplating multiple attachment means for securing the lid 400 in a closed position, the present invention contemplates alternate embodiments of the strap and strip closure system. For example, the number and placement of top closure straps and side closure strips may vary in alternate embodiments. For example, in one embodiment (not shown), the collapsible container 100 may comprise only one top closure strap attached at one end to the inelastic wrap tray 300 and hanging free at the other end for attachment to a single side closure strip for maintaining the lid 400 in a closed position. In another embodiment (not shown), the lid 400 of the collapsible container 100 may comprise only one top closure strap disposed on the top surface 425 thereof and hanging free at both ends for attachment to two side closure strips disposed on opposed outer planar surfaces of the continuous rigid structure in alignment with the free ends of the top closure straps.

Turning now to an embodiment of the present invention further comprising additional means for secure closure of the lid 400 and containment of contents within the collapsible container 100, FIGS. 4B and 4C clearly depict an embodiment of the present invention comprising a truss member 600 that prevents top rim 222 of the continuous rigid structure 200 from bulging beyond the footprint of the lid 400. The truss element 600 is an inelastic, closed loop that passes through each of three inwardly facing closed retention loops 265, 270, 275 and a fourth, independent inwardly facing closed retention loop 280. The truss element 600 may be made from robust, wear resistant materials such as, but not limited to, polypropylene or polyester. The truss element 600 is fed through each of the three inwardly facing closed retention loops 265, 270, 275 and the fourth, independent inwardly facing closed retention loop 280, tensioned and bound end-to-end or with free ends overlapping to form a securely tensioned closed loop. The ends of the truss element 600 may be bound by methods such as for example, but not limited to, sonic welding, stapling, riveting, tying, gluing or thermally bonding.

The truss element 600 therefore prevents the top rim 222 of the continuous rigid structure 200 from bulging under load conditions. Additionally, because the at least three inwardly facing closed retention loops 265, 270, 275 and the fourth, independent inwardly facing closed retention loop 280 are short, unobtrusive, and disposed directly adjacent the top rim 222, the truss element 600 disposed therethrough is tensioned about the periphery of the collapsible container, thereby providing sufficient clearance for loading and unloading contents into and out of the collapsible container 100. If the top rim 222 were to bulge, that would affect proper secure closure of the lid 400. Holding the top rim 222 within the footprint of the lid 200 prevents loss of contents or creation of bulged openings at which moisture or debris could fall into the collapsible container 100, contaminating and/or damaging contents.

Furthermore, threading the truss element through each of the three inwardly facing closed retention loops 265, 270, 275 and the fourth, independent inwardly facing closed retention loop 280 precludes any necessity for puncturing the continuous rigid structure 200 to accommodate the tensioned truss element 600. Prior art containers and bags require puncturing the sidewalls of those assemblies, thereby creating zones of weakness at which the structures could stretch, tear and/or allow loss of content. In some prior art devices having trusses threaded therethrough, additional hole reinforcements and encapsulating structures are required to shield against stretching, tear, seepage and loss of contents. Those additional structures add complexity to the manufacturing process of those devices, add weight to the completed container assemblies, and prevent collapse of those structures to a low profile, planar state as compared to the collapsible container 100 of the present invention which requires fewer bulky components which achieving robust load bearing capabilities.

Turning now to an embodiment of the present invention comprising a liner, FIGS. 4B and 4C depict an impervious liner 700 pre-installed within the interior of the collapsible container 100. In one embodiment, the liner 700 is form-fitted to the four planar sides 205, 210, 215, 200 of the continuous rigid structure 200 and uniformly, permanently affixed thereto by glue, epoxy, resin or any other adhesive that is known in the art. The liner 700 is affixed to the four planar sides 205, 210, 215, 200 such that the liner 700 is coplanar with each of the four planar sides 205, 210, 215, 200. That is, the liner 700 is affixed across all of each interior surface of the four planar sides 205, 210, 215, 200. In another embodiment, the liner 700 is tacked to the inner surfaces of the four planar sides 205, 210, 215, 200. For example, the liner 700 may be tacked about the top rim 222 of the collapsible container 100 and in one or more spots closer to the bottom member 325 of the collapsible container so that the liner remains in place without puckering, slipping or folding in on itself during filling and evacuation of the collapsible container 100. The liner 700 is preferably composed of a water resistant or water proof synthetic material that is also resistive to degradation by temperature and corrosive compounds. For example, the liner 700 may be manufactured from materials such as, but not limited to, polyurethane, polyethylene, polyethylene film, polymethylpentene (PMP), polypropylene, or nylon.

In one embodiment, the liner 700 may be a disposable type liner easily removed and replaced with a clean, new liner 700. Additionally, a sturdy but impermanent retaining feature (not shown) may be disposed on the inner surface of the planar surfaces 205, 210, 215, 220 and/or the bottom member 325 for retaining a disposable liner 700 within the drum 100. For example, in one embodiment, the retaining feature may be a Velcro® system, with a sizeable Velcro® panel secured to the inside surface of the bottom member 325 and a mating Velcro® portion secured to the liner. Securing at least one Velcro® panel on at least a third of the inner surface of the bottom member 325 enables retention of the disposable liner 700 during contents evacuation. As one of skill in the art will recognize, other retention systems are capable of producing the same result such as but not limited to snaps, zippers, hook and latch, tie downs, and static charge. Such liners enable transport of hazardous and/or liquid materials without degrading the components of the collapsible container 100 and thereby increase the potential number of reuses of a collapsible container 100.

Turning now to FIG. 5, in all embodiments of the present invention, the collapsible container 100 collapses to a low profile planar structure for easy handling and compact stacking for storage and transport. FIG. 5 illustrates the collapsible container 100 in a state of collapse, with the collapsible container 100 buckled at the score lines 225 for compression like a bellows. The lid 400 is folded back 270 degrees from its closed position so that the top surface 425 contacts the outer surface of the “hinge side” planar side 205 of the continuous rigid structure 200. The fully integrated lid 400 therefore remains attached during collapse and storage of the collapsible container. This eliminates potential for loss of that permanently attached member, eliminates a need for re-securing the lid 400 to the continuous rigid structure 200 during each use of the collapsible container 100 and establishes a mechanism for an efficient, single movement to close the hingedly attached lid 400 atop the expanded collapsible container 100 during use. Unlike existing semi-rigid containers, the collapsible container 100 of the present invention is collapsible into a small volume, low profile, substantially planar state for easy, efficient storage and transport.

The collapsible container 100 of the present invention as described herein provides a number of tangible benefits over the existing rigid and semi-rigid containers known in the art. The collapsible container 100 of the present invention is rigid enough for stacking, storing and transporting a variety of materials that other semi-rigid containers cannot handle. Moreover, unlike the rigid metal containers, the collapsible container 100 of the present invention can be collapsed from a substantially cubic volume into a substantially flat square for easy stacking and storage.

It is noted that the foregoing examples have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the present invention. While the present invention has been described with reference to an exemplary embodiment, it is understood that the words, which have been used herein, are words of description and illustration, rather than words of limitation. Changes may be made, within the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of the present invention in its aspects. Although the present invention has been described herein with reference to particular means, materials and embodiments, the present invention is not intended to be limited to the particulars disclosed herein; rather, the present invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims. 

1) A collapsible industrial shipping container comprising: a) a continuous rigid structure having four planar sides defining four inner surfaces and four outer surfaces, two opposed planar sides each having a scoring line rendering the continuous rigid structure collapsible; b) a five-walled inelastic wrap tray made of a flexible, inelastic fabric affixed to a lower portion of each the four outer surfaces and defining a bottom surface of the collapsible industrial shipping container; c) at least three side closure strips fixedly disposed on the outer surfaces of three consecutive planar sides, one end of each of the at least three side closure strips securely connecting to the inelastic wrap tray, the other end of each of the at least three closure strips terminating in an inwardly facing closed retention loop positioned adjacent the top rim of the continuous rigid structure; d) a closure means fixedly positioned along the length of each of the at least three side closure strips at a point below the top rim of the continuous rigid structure and above the five-walled inelastic wrap tray; e) a lid defining at least one hingedly attached flap affixed to the fourth outer surface such that a fourth inwardly facing retention loop is securely affixed between the flap and the fourth outer surface and positioned adjacent the top rim of the continuous rigid structure, wherein a system of one or more top closure straps affixed to the top surface of the lid are adapted for engaging with the attachment means; and f) an inelastic member that passes through each of the inwardly facing closed retention loops of the at least three side closure strips and the fourth inwardly facing retention loop, thus preventing the top rim of the continuous rigid structure from bulging under load conditions. 2) The container of claim 1 wherein the closure means is an outwardly extending loop formed in each of the at least two side closure strips. 3) The container of claim 2 wherein the closure means further comprises an eyelet formed in the outwardly extending loop for receiving a tie therethrough. 4) The container of claim 2 wherein the outwardly extending loop further comprises a metal ring securely affixed thereto. 5) The collapsible container of claim 1 wherein a five-walled inelastic wrap tray is made of a material selected from a group consisting of woven polypropylene, woven polyurethane, reinforced polyethylene, woven fiberglass, and other polymeric materials. 6) The collapsible container of claim 1 wherein the inelastic member is comprised of polypropylene or polyester. 7) The collapsible container of claim 1 wherein the inelastic member is polypropylene. 8) The collapsible container of claim 1 wherein the inelastic member is polyester. 9) The collapsible container of claim 1 wherein the inelastic member is comprised of a single length of material that is fastened to itself to form a continuous member. 10) The collapsible container of claim 9 wherein the inelastic member is sonic welded to itself to form a continuous member. 11) The container of claim 1 wherein the continuous rigid structure is comprised of fiberboard. 12) The container of claim 11 wherein the fiberboard is coated with a water resistant coating. 13) The container of claim 11 wherein the fiberboard is doubled walled. 14) The container of claim 1 wherein the lid is comprised of singled walled fiberboard. 15) The container of claim 1, further comprising an impervious liner disposed within the continuous rigid structure. 16) The container of claim 15 wherein the liner is form fitted and uniformly adhesively affixed across substantially all of each interior surface of the four planar sides 17) The container of claim 15 wherein the liner is fixedly adhered to the inner surfaces of the four planar surfaces but only adjacent the top rim of the continuous rigid structure. 18) The container of claim 1 further comprising an eyelet disposed in each of the ends of the top closure strip. 19) The container of claim 18 further comprising a tie element suspended through the eyelet for engagement with the attachment member. 20) The container of claim 1, wherein the system of one or more top closure straps comprises at least one top closure strap extending across the top surface of the lid and having both free ends aligned with two of the at least three side closure strips. 21) The collapsible container of claim 20 wherein the at least one top closure strap is made of a material selected from a group consisting of woven polypropylene, woven polyurethane, reinforced polyethylene, woven fiberglass, and other polymeric materials. 22) The container of claim 20 wherein the free ends of the at least one top closure strap are adapted for engaging with the closure means fixedly positioned along each of two of the at least three side closure strips. 23) The container of claim 22 wherein the free ends of the at least one top closure strap support eyelets fixedly secured therein for receiving a tie strap. 24) The container of claim 1, wherein the system of one or more top closure straps comprises at least one top closure strap attached at one end to the wrap tray, extending across the fourth outer surface and the top surface of the lid, and having a free end aligned with the closure means on the opposed planar side. 25) The collapsible container of claim 24 wherein the at least one top closure strap is made of a material selected from a group consisting of woven polypropylene, woven polyurethane, reinforced polyethylene, woven fiberglass, and other polymeric materials. 26) The container of claim 24 wherein the free end of the at least one top closure strap is adapted for engaging with the closure means fixedly positioned along each of the at least two side closure strips. 27) The container of claim 25 wherein the free end of the at least one top closure strap supports an eyelet fixedly secured therein for receiving a tie strap. 